The seminar for which the proceedings are published here evolved from a cooperative research program on bilinear systems and applications to immunology at the Oregon State University and at the University of Rome. The topics include more general forms of variable structure systems which may be divided into categories of mathematical system theory, economic applications and biological applications. Throughout the seminar there was emphasis on the integration of theory and app- cation. In most cases, theoretical derivations are motivated by their need to solve practical problems. In reading the proceedings, it becomes apparent that bilinear systems, quadratic systems and more general variable structure or adaptive systems become natural models in many cases and excellent approximations in others. It is seen that linear systems have very limited use particularly in economics and biology. Variable structure systems are analyzed in terms of structure,volterra kernels, system modelling, parameter identification,- controllability and Lie algebra to mention a few. Certainly, it ia nbt possible to present a complete tre- ment of these numerous topics, but at the Same time the unifying power of the systems approach and variable structure systems is shown.

Inhalt
A Topological Space of Systems and a Dense Subset.- On Quickest Detection of System Structure Variation.- Stochastic Partial Differential Equations in Optical Communication Problems.- A Bounded Rate Model for Mass Action Multiple Binding Processes: Stability Analysis.- Expectations and Dynamic Stability in Economic Models.- Optimal Control of Information Structures.- Mathematical Models of Blood Coagulation Kinetics.- Stability Problems in 2-D Systems.- On Mathusian Models of Migration and Population Growth.- Minimal Realizations of Linear and Affine Time-Varying Systems.- Continuous Linear Programming and Piecewise Bilinear Systems.- Optimal Bilinear Control Theory Applied to Pest Management.- Linear Descriptor Variable Systems.- Genericity and Singularities in Vector Optimization.- Variable Metric Methods and Filtering Theory.- Overview of Recent BLS Research and Immunology.- Innovations Informational Equivalence in the Independent Gaussian Case.- Structure and Realization of Decomposable Biaffine Systems.- Bilinear Models in Ecology.- Applications of Optimal Control Theory to Immunology.- On the Internal Structure of Finite-State Stochastic Processes.- Public Information Activities: Evaluation with Variable Coefficient Models.- Time Reversibility in Deterministic and Stochastic Dynamical Systems.